EMD SD70MAC
Bio The EMD; Electro Motive Division; SD70MAC is a type of six-axle 4,000hp diesel locomotive built from 1995 to 2001, and briefly resumed until around 2005. Over 200 were built, with only 20 built specially for Conrail and over 100 built for the Burlington Northern (with orders continued into the BNSF merger with another 100 or so units ordered later on). Later customers such as CSX, ONR, the Alaska Railroad (ARR) and TFM (subsidary of KCS; Kansas City Southern) eventually purchased units up until the introduction of the SD70ACe. The SD70ACe serves as the SD70MAC's replacement; having more advanced microprocessor controls and convertable electric currents. Many are still currently in service, with the exception of several stored, wrecked, rebuilt, and retired units. History During the early-1990's, EMD teamed-up with German engineering company Siemens (producer of most modern, high-tech diesel and electric locomotives and train sets) to experiment with having an average, modern North American diesel locomotive to become capable of providing AC-traction drive currents, and providing high-horsepower for railroads which had an ever-increasing demand for saving fuel consumption by using a lesser amount of units to haul most of their trains. The solution to all these problems was resolved with the experimental SD60MAC, which proved to be an initial success after several demonstrations with the Burlington Northern's Powder River coal trains through Wyoming and Montana. Thus, because of the success of the SD60MAC, the development for the SD70MAC became an initial response. Although the SD60MAC was successful, the BN; however, disliked the cab design due to being uncomfortable with rail employees who tested the units. Such complaints consisted of: heavy vibrations, noise pollution from the prime mover, and an unusual amount of cab visibility due to the cab design originating from an earlier SD60M, yet with a slightly different window placement which deemed to be too "foreign"; meaning that the design looked more Canadian, and was originally disliked by employees who drove some of BN's earlier SD60M units. The EMD SD70MAC was first introduced in 1994, and began production in 1995 after numerous tests and improvements were made. The first orders of 75 units were received from the BN in mid-1995, with orders placed the previous year. BN eventually began to slowly replace their fleets of aging SD40-2 units (aside from their GE U30C and Dash 7 units) assigned to their Powder River Coal Trains in favor of their new, modern, high-tech AC-traction SD70MAC units; which were proven to replace 5 to 7 SD40-2 units on an average coal train, with only 3 to 4 being necessary (two front, two rear) with the SD70MAC units having a DPU (Distributed Power Unit) capability, which was originally introduced with the SD60MAC. The SD70MAC is similar in design to the SD70M, having a slightly longer frame to comensate for large traction components (unlike the GE AC4400CW, which is actually meant to be a completely different locomotive which really isn't), with additional exterior and interior components which primarily help distinguish the SD70MAC's AC-traction drivers, traction motors, and microprocessor control features. (The radiator cabinet cover being the main noticable difference, aside from a large gap being present at the rear hood of the actual locomotive.). Towards the end of the SD70MAC's introduction, a new rival from GE appeared: the AC4400CW, which completely dominated over the SD70MAC in production sales. Although more successful in popularity, the AC4400CW had more short-lived warrenties with most railroad's fleets which had to be renewed unlike the SD70MAC; hence the reason why the Burlington Northern decided to deny every opportunity from GE due to already having numerous warrenties from leasing companies which required numerous payments. Today, the SD70MAC can still commonly be seen hauling various coal trains or being assigned to coal drag service on the BNSF, as well as being a common hauler on the TFM portion of the KCS (Kansas City Southern). Former Conrail SD70MAC units can still be seen on the CSX system, yet no longer bear or wear their once-exclusive livery which was very similar to their SD80MAC livery, while the Alaska Railroad's fleets of SD70MAC units (as with ONR) can still be seen in general revenue service on both of their freight and passenger trains (being the only US Class 2 railroad to actually have both revenue freight and passenger service like with the ONR of Canada.) Trivia/Facts Conrail's SD70MAC fleet was originally meant to be compatable with their SD80MAC fleet as well, yet their SD70MAC's commonly served as helper or DPU units on trains led by SD80MAC units. CSX's SD70MAC fleet primarily consists of all 20 former Conrail units, yet they eventually ordered another small fleet shortly before ordering SD70M (and SD70I converted) units. The SD70MAC was the last type of locomotive ever purchased by the Burlington Northern before merging with the Santa Fe (ATSF) in 1995-1996, which also wore a short-lived exclusive paintscheme which was also applied to their executive fleet of preserved F Units and coaches from their predecessor's heritage. Although the BNSF merger continued into 1996, EMD still applied the BN's exclusive "Cascade Green" scheme to BNSF's new orders of SD70MAC units shortly after BNSF officially established their "Heritage 1" scheme. BNSF's later SD70MAC units had different headlight and handbrake placements as opposed to their earlier pre-merger/post-merger BN SD70MAC units. Norfolk Southern (NS) originally intended on ordering SD70MAC units, but received SD70I units (isolated cab version of the SD70M) instead. BNSF often uses their former BN "Cascade Green" paintscheme to distinguish their SD70MAC units from their former ATSF SD75M units; most which still wear the ATSF's "Warbonnet" scheme. Only four SD60MAC units were built, with only one remaining in storage as of 2012. One SD60MAC unit was actually rebuilt into an SD59MX demonstrator in 2010-2011. BNSF #9647; the "Vomit Bonnet", was painted in an exclusive livery to commemorate the success of the BNSF merger, and actually demonstrates an experimental scheme. Only a handful of SD70MAC units have actually been painted into BNSF's New Image ("also known by fans as H3, or Heritage 3") scheme. Like with their other fleets of AC-traction diesel locomotives, CSX adds or paints distinct "lightning bolts" on the sides of the cab just below the numbers on their SD70MAC units (including their SD70I units.) Later ARR SD70MAC units were fitted with Tier I ratiators similar to those on CSX & UP SD70M orders. ARR #4001 was actually applied with a unique dedication known as the "Spirit of Alaska", similar to CSX's "Spirit Of..." units. The Paducah And Louisville Railroad (P&L) recently acquired 16 former CSX SD70MAC units and is expected to acquire 46 total by the end of 2013 (units also included are SD70AC/SD70I units). Gallery BNSF SD70MAC units.jpeg|Two BNSF SD70MAC units from two generations: pre-merger and post-merger. TFM SD70MAC.jpg|An example of a TFM SD70MAC. BNSF 9647.jpg|BNSF 9647; the "Vomit Bonnet" SD70MAC unit with one of their experimental paintschemes. CSX SD70I units.JPG|Two CSX SD70I units which are often designated as an "SD70AC" or an "SD70MAC", yet these units weren't actually produced under the SD70MAC production line. Original CN SD70I.JPG|An example of an original CN SD70I showing it's dinstinct "whisper cab" seal at the front hood or "nose" of the cab front. Alaska Railroad SD70MAC.jpeg|An example of a later Alaska Railroad SD70MAC showing its distinct SD70I components. ARR SD70MAC.jpg|An earlier Alaska Railroad SD70MAC, which consists of SD60 components. (Unit shown, is actually ARR #4001: "Spirit of Alaska". ARR 4001.jpg|ARR #4001: "Spirit of Alaska", wearing a Christmas reef. Conrail SD70MAC's.jpg|Another example of some of Conrail's original SD70MAC units. P&L SD70MAC.jpg|P&L #4502: a former CSX SD70MAC. Sources http://www.thedieselshop.us/Data%20EMD%20SD70MAC.HTML Category:Diesel Locomotives Category:EMD locomotives Category:AC-traction Diesel Locomotives